


Boom Boom Boom by the Vengaboys except it's a Japanese volcanic island.

by RussianSunflower3



Series: Sunflower's WHUMPTOBER 2018 [21]
Category: Haikyuu!!
Genre: Fluff and Hurt/Comfort, Fluffy Ending, I love volcanology so much, M/M, Multiple referenced volcanoes!!!!, Nishinoshima island, Volcanic Eruption, Volcanologist Au!!!!, Whumptober 2018, aged-up third years, harsh climate
Language: English
Status: Completed
Published: 2018-10-21
Updated: 2018-10-21
Packaged: 2019-08-05 04:23:10
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,183
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/16360706
Author URL: https://archiveofourown.org/users/RussianSunflower3/pseuds/RussianSunflower3
Summary: The split second Oikawa gets the A-Okay to do some research on the newest volcanic island in Japan, he isthere.But he's not the first, and in a field as small as volcanology, it's not surprising he knows the other people gathered on the docks.He doesn't expect their small expedition to be int-erupted.No, literally, it's erupting.





	Boom Boom Boom by the Vengaboys except it's a Japanese volcanic island.

The field of volcanology was a small one, so when something big went down, it attracted those few volcanologists to it like _flies_. Like bees to honey. The best part was when something happened close to where one was studying, so they could flock there within hours.

And that was exactly what happened to one very lucky Oikawa Tooru.

He’d already been in Tokyo, collecting analysed data from the university where he’d had rock samples tested, when he got the call about volcanic activity. 

And it was close by. _Very_ close by.

Oikawa had rushed to the docks, but much to his surprise, he wasn’t the first one there.

“Makki? Iwa-chan?” As stated before, the field of volcanology was a small one, which meant many people knew each other. Especially if they spoke the same first tongue, or came from the same hometown.

Hanamaki blandly lifts a hand in greeting with a ‘yo~’, whilst Iwaizumi nods his head.

“Oikawa. Haven’t seen you since Sakurajima. How’s it going?”

“It’s going great! I got some soil samples tested from Mount Aso, to see if the caldera has experienced recent collapse!” As Oikawa rambles on, Hanamaki half pays attention, more focused on waiting for their boat to arrive, whilst Iwaizumi nods along with smiles and small interjections.

Oikawa is always so enthusiastic that Iwaizumi can’t help but listen to him, like a lovestruck fool.

“Oiiii, bitches.” Three stunned faces whip around to see another coming, and Hanamaki grins slyly as he waves.

“Thought you were in New Zealand, Matsukawa?” Matsukawa catches up to them, high-fiving Hanamaki, whacking Oikawa’s back, and ruffling Iwaizumi’s hair to knock him off balance.

“I was! Havre was _awesome_ , but we’d just got back last night and stayed at the airport hotel.” Oikawa makes to ask about Havre, the underwater volcano, when Iwaizumi interrupts by holding a hand out flat.

“We?” There’s a moment where Matsukawa blinks, before realisation suddenly dawns on him.

“... I left the interns in the car.” He spins on foot and runs off again, to the laughter of his friends, before Hanamaki calms down first.

“Interns, huh? I guess I should take one on now, since I’ve completed the last project.”

“Ack, I haven’t even _thought_ about interns.”

“That’s because Iwa-chan is so selfish~. Ow, don’t hit me! Actually, I’m surprised Mattsun took on some interns, after that spat he had with Yahaba…” Iwaizumi laughs, remembering Oikawa’s intern that went off on his own last year.

“They got along _great_ until it came down to the date Vesuvius erupted!” Hanamaki inspects his nails, clearly bored of the conversation, but chimes in anyway.

“We were all taught it happened - without doubt - in August, so I can see why Matsukawa stuck to his guns. Yahaba was still a student, right? He was more open to change.” The three go quiet as they think deeply, the waves lapping at the shore lulling them into comfortable silence. And then, a distant voice.

“-over this hill. Sorry for leaving you behind, I thought you’d keep up.”

“Your bags are heavy, Matsukawa-senpai.” That is… A young voice. Very young. Matsukawa comes back over the hill, with two _high schoolers_ trailing behind him, one of them carrying the lighter equipment, the other struggling to pull a cart of the heavy stuff.

“You can’t complain, Kunimi, you didn’t draw the short straw.” Matsukawa gestures towards his other, struggling intern, doing nothing to help, but also slowing his pace. Kunimi spots the other three waiting on the docks, and like a sudden shyness has overcome him, shuffles behind Matsukawa.

“Iwaizumi, Oikawa, Hanamaki, I want you to meet my interns!”

“Mattsun, those are 15 year olds.”

“Yeah? Gotta start them young, before the interest dies.”

“Huh, morbid.” Kunimi snorts a laugh at Iwaizumi’s dry response, prompting an encouraging grin from him. They might only be 7 years their seniors, but that won’t stop them from metaphorically adopting the teenagers.

From the water comes a drone, a boat approaching the dock, and Hanamaki stands up from the post he’s been leaning against, ready to board as he picks up a locked briefcase.

“This is for us~. Ready for your first field trip, kids?” Kunimi rolls his eyes.

“We’ve been to New Zealand.”

“ _Second_ field trip then. This one on a volcano that’s broken the surface.”

“Can someone please help me?!” As the boat comes into dock, Hanamaki and Oikawa securing the rope to tie it in place, Iwaizumi and Matsukawa makes their way - rapidly - to the boy desperately trying to stop the heavy equipment rolling down the hill by standing in front of it, pushing against it.

“Easy, Kindaichi, take a deep breath… We’ve got this.” Iwaizumi mentally takes note of the boys name, helping Matsukawa get the equipment down a hill.

“Holy fucking shit, that’s a lot of stuff.” Matsukawa shrugs once they have it on flat ground, glancing out the corner of his eye to make sure Kindaichi is stretching out his shoulders, as he’s ordered his interns to do when handling heavy luggage.

“Just came from New Zealand. What did you expect?” Iwaizumi laughs, knocking his knuckles against Matsukawa’s shoulder.

“Get on the boat, moron~.” It takes a ridiculous amount of time, but finally, with all equipment and members on board the research vessel, with no signs of others showing up, the boat departs the bay towards a volcanic, harsh environment.

Nishinoshima, an island forming from a seamount volcano, had enlarged in 1974 to the point where it was officially considered stable, the explosive type volcano spitting out ash, lava, and pumice to build its foundations. 

The rocky island was harsh and barren, not a plant in sight, and the air filled with choking ash and sulphur.

“Masks on, guys.” Oikawa’s calm voice is not one to argue with, his eyes narrowed analytically at the volcano as they approach. It’s still warm, so warm that they have to wear protective clothing, but the alert this morning was that Nishinoshima had been cleared for testing.

Henceforth, why the volcanologists were here. Surely, more would flock from around the country and _worldwide_ , but for now, they were the only six here. 

“Everyone got their gear on?” Matsukawa pulls up the zip on the back of Kunimi’s protective suit, giving Oikawa the OK symbol, same as Iwaizumi and Hanamaki. They can talk, but it’s kind of a ritual for when they step on a new island.

It’s like entering another world, and the silence helps preserve that moment.

(Oikawa had fully intended to deck a former colleague, Ushijima, for breaking that silence once. Ushijima only escaped punishment because Hanamaki held Oikawa back and Iwaizumi knocked some sense into him. Not all volcanologists had to follow their strange ritual.)

Hanamaki steps onto the island first, simply because he was waiting at the docks first. Iwaizumi hauls himself up after him, and they’re the two that start to unpack the equipment after Oikawa, Matsukawa and the interns pass it up.

It’s hard to keep balance on uneven ground.

Once they’re all on the island, Oikawa heaves a sigh and pats one of the robot rovers on the ‘head’.

“Well! Let’s get sample collecting! Hope you don’t mind, but I’m claiming rock composition and layering.”

“Dammit, Oikawa! I wanted that!” Oikawa sticks his tongue out at Iwaizumi through the cloth mask, giving him double peace signs that Iwaizumi tries to wrestle with.

“Whilst the lovebirds flirt, I’m gonna grab data from the seismographs. You okay with that, Matsukawa?”

“Yup. Gotta teach the kids how to use an EDM anyways.”

“I'm already familiar with electronic dance music.” Kunimi states blandly, though there’s a smirk on his face and Matsukawa’s eyebrow twitches.

“For the _eighth_ time, _**no**_. Electronic distance measuring!”

“Electronic… Dance music~.” Matsukawa growls in frustration, sliding a hand down his face.

“I pick you out of 200 applicants. I make you my intern. I _feed_ you, both food and knowledge. And _this_ is how you replay me?!”

“Matsukawa-senpai, where do you want the… Uh… Thingy! Where do you want the thingy?” Kindaichi holds up a grey suitcase, obviously not remembering the name of the thing inside, but he beams so brightly and enthusiastically that it’s impossible to be mad.

“I’ll take it. Come on, let’s get you guys educated!” He leads the interns away, and Hanamaki laughs at the sight of it, like two ducklings chasing after mother duck, one occasionally straying before coming back, the other stumbling and desperately trying to not be left behind.

He sighs, turning back to Iwaizumi and Oikawa, who have quietened down and are no longer fighting. In fact, they’re just calmly talking to each other, like they weren’t trying to tear each others throats out a moment ago.

“Iwaizumi, you need to make up your mind what you wanna do.”

“I’ll take gas measurements from the fumaroles. It’s the _second_ best way to see inside a volcano, I guess.” Hanamaki pats his shoulder in sympathy, knowing Iwaizumi loves to do rock samples. But, they’re Oikawa’s speciality, so it’s no surprise the most famous of them made that his choice.

If anyone is going to read this volcano like a book, it’s world-renowned volcanologist Oikawa Tooru. 

Once they’ve separated into four directions, the island falls into silence asides from the waves lapping at Nishinoshima’s rocky fringes. Matsukawa softly and patiently explains how to use the EDM gun to his interns, both of them invested in their own ways.

Eventually, he lets Kunimi work the computer imagine whilst he guides Kindaichi around with the gun. Walking from one spot where seismographs are buried to the next, Hanamaki stops to watch them for a second, huffing in fond amusement.

They still look like his ducklings, like a little family.

Maybe, if the two decide to carry on down the volcanologist route after this internship, they’ll come to learn the entire field is like a family. The thought is warming, but they’re still only 15 for now, so they’ll have a long while to go.

“Fancy meeting you here.” A grinning Oikawa comes up behind him and Hanamaki tilts his head in curiousity at the feather he’s holding.

“Where’d you get that from?”

“From a nest~.”

“A nest?”

“A nest, on the island!” Oikawa’s excitement is nothing to laugh at. It’s _genuine_ , because that means there’s _wildlife_ on this island! The first signs of life have settled on Nishinoshima, sea birds nesting here to feed their chicks on the rich diet that explodes from the islands nutritional waters.

“That’s incredible!!! We need to get this officially registered! Nishinoshima could be a protected area for wildlife!”

“I know, right~! It’s amazing!” Hanamaki takes a moment to celebrate with Oikawa, before bidding him goodbye back to his rocks, and heads to the closest spot where equipment was buried in 2014.

The seismographs have been recording data all this time, and once Hanamaki downloads it onto his laptop, he’ll be able to read all that data from start to finish. He finds the flag marking where it’s buried and kneels down, spotting Iwaizumi taking gasp samples from a fumarole not too far away.

A quick wave is all Iwaizumi spares him, incredibly focused on his work. That… Somewhat worries Hanamaki. Usually, Iwaizumi is all up for a chat, but when he focuses… It means his readings must be either inconclusive, or dangerous.

The last one, with two 15 year olds on the island, Hanamaki doesn’t want.

He hooks his laptop up, downloads the information he needs, and decides to prematurely look at the data from the four stations he’s gathered. There are 6 more, but he’d like to put his mind at ease.

“Hanamaki.” He jumps just as he’s pulling up the digital seismograph screen.

“Geez, Iwaizumi, let me keep my socks!”

“... What?”

“Cus you almost scared the socks off me!”

“... Yeah. Whatever. Listen, this is gonna sound weird, but…” He crouches down, as if sharing a secret, but Hanamaki knows it’s much more serious.

“I want to get the kids off this island as soon as possible. Think you can call the boat back?”

“I… Can. But why? I mean, I saw you were all serious and stuff, but is it really that bad?” Iwaizumi nods, brow furrowed.

“The levels of gas being emitted are astronomical. And the _types_ of gas too, a fuckton of carbon dioxiade, a hella load of sulphur… It’s making me uneasy.” Hanamaki makes a quick call to the scientific research vessel.

“It’s on its way. Wanna double check the seismograph with me for peace of mind?” Iwaizumi nods, crouching next to where Hanamaki’s sat cross-legged, and scroll through to find the last three days.

What was meant to be reassuring…

“We need to evacuate. Now.”

… turns out to be the complete opposite. 

The graph is littered not only with A-signals, which is the sound of the rock breaking inside the volcano, but with _B-signals_ , the distinct sound of something pressurizing, of magma surging up through the cracked rock. They’re especially frequent in the past few hours.

Nishinoshima is going to blow.

Hanamaki hurriedly packs up his laptop whilst Iwaizumi races off to find Matsukawa and his interns, and Oikawa. They’ll have to abandon the large equipment for now. This is an emergency.

“Makki! Makki, is it true?!” Oikawa, who didn’t have anything to pack up since his rock samples were all attached to a belt, catches up to him quickly. 

“That this place is gonna blow and take our asses with it if we don’t evacuate immediately? Yeah, it’s true.”

“Well, shit.” Those two reach the rocky fringes of the island first, where the boat can safely line up with Nishinoshima to allow them to board, anxiously waiting for the boat. 

“Ah, here comes Iwa-chan~.” Iwaizumi runs over towards them, holding hands with both the children, Matsukawa behind him making sure no one trips. They could easily get a dirty cut if they fell on this ground, the harsh climate of the volcanic island making for easy scrapes.

The boat engine can be heard approaching, and Hanamaki beams with relief and joy, until he hears - no, _feels_ \- something else rumbling.

The volcano.

Nishinoshima is _erupting_ , and they’re still on it. 

Oikawa doesn’t wait for the boat to be properly lined up with the island, instead leaping recklessly across a large gap of ocean and landing on the deck, reaching out for Hanamaki to pass down his laptop, and the briefcase Matsukawa brought with him, if he packed up the EDM.

It doesn’t look like it. He’s not carrying anything, just ushering the teenagers along and they look _terrified_. Hanamaki remains where he’s kneeling on the edge of the island, and helps Kunimi over the small oceanic gap, so Oikawa can reach him and pull him into the boat.

“Come on, come on, it’s okay.” Kunimi moves to the other side, sitting down on a bench with trembling hands as he waits for his best friend to join him. But before Kindaichi can make it in, the boat lurches a little further away.

"Kin-chan, you're going to have to jump. Can you do that? I'll catch you, promise."

“I- I don’t think I can!” The earthquake from the volcano makes the water ripple, rocking the boat back and forth, far too close and then further away. Matsukawa squeezes Kindaichi’s shoulder reassuringly.

“We’re right behind you, don’t worry. You can do this.” Taking in a deep breath, Kindaichi backs up a little and makes a running start, leaping into Oikawa’s arms in the boat. He’s quaking all over, eyes squeezed shut in pure fear, and Oikawa ushers him to sit besides Kunimi where the two practically sit on each other’s laps.

But just as Hanamaki gets in the boat, another ferocious earthquake shakes the island, the water sloshing and pushing the boat too far away for Matsukawa or Iwaizumi to cross, and the cone of Nishinoshima spits out rock, smoke, and ash.

No doubt, there’s lava in there too. Iwaizumi knows that as soon as the plume of smoke starts to fall, it’s sweep across the small island and then stretch across the water, potentially as a pyroclastic flow. If the boat were caught in that… 

None of them would survive.

“Go! _Go_!” His desperate shout can be just heard above the sound of the volcano, and he watches as Oikawa’s face falls from stressed to _hurt_ , like he’s just had his heart ripped out of his chest.

“Iwa-chan…? Mattsun? Iwa-chan! No, no, don’t leave them there, go back! IWA-CHAN!” The boat draws further away, but Iwaizumi can still hear Oikawa screaming and see Hanamaki trying to hold him back, and the kids watching with fear, their eyes shadowed over with trauma.

“Iwaizumi.” A hand wraps around his wrist and gently tugs. With tears in his eyes and fist clenched together, he turns away from the boat, from any signs of escape, and lets Matsukawa lead him _towards_ the volcano.

“If we can find a big enough boulder to shelter behind, we might be able to avoid being caught in the flow… Just severely burn from the heat.”

“Matsukawa.”

“Or we might luck out and it’ll fall away from us.”

“Matsukawa.”

“I think I saw something over this way-”

“Matsukawa!” Iwaizumi snatches his wrist away, stopping in his tracks. Matsukawa slows to a stop, looking back at him over his shoulder as if he’s crazy.

“Wh- What are you doing, Iwaizumi…? We need to hurry!” 

“We’re going the wrong way. I saw a boulder probably big enough over here, if I sit in your lap…” Despite the situation, Matsukawa can’t help but smirk and crack a joke.

“Well, well, if I’d known all it took was a volcanic eruption, I’d have taken you to Etna some time~.” Iwaizumi snorts, rolling his eyes and slapping Matsukawa’s shoulder. Another boom from the volcano, and they pick up the pace.

The boulder the come to is tall and wide enough for a single person, and the top of it curves over slightly like a roof - the perfect shelter.

Matsukawa shuffles under it, legs slightly apart, and pats the spot invitingly for Iwaizumi to settle down. Of course, he hides his face behind his hands with a snort that’s a mix of embarrassed, amused, and annoyed, but gets into position anyways, tucking his head neatly under Matsukawa’s chin, his back to Matsukawa’s front.

“Of all the people I had to get stuck with, it had to be you.”

“Yeah, I bet you would have _loved_ for it to be Oikawa. It’s hard work keeping you two from making out as it is.”

“Ex _cuse_ me, we do not ‘make-out’! We talk about our work! And maybe our weekend. And maybe our personal lives…”

“And how you’re going to get married one day, and adopt seven dogs and three kids and-”

“Shut up!” Red as a tomato, Iwaizumi buries his hands in his face with a pained groan. Matsukawa laughs, cutting off with a cough. Whilst they still have their marks on, the ash raining down now is fine like snow, and still has the potential to get in their lungs.

Even if they make it out of here alive, they’re going to need hospital.

“Hey. Speaking of kids.”

“Is this a proposition, Iwaizumi~?”

“ _No_ , shut up. I was wondering why you were adamantly against interns, and then suddenly pick two high schoolers for the job.” There’s an odd pause, and Matsukawa frowns, mood sobering.

“I… I wasn’t going to take on interns. Ever. But then these kids came up to my office and they held out these applications with such determination… I was still going to turn them down. But…” He trails off for a moment and Iwaizumi waits patiently until Matsukawa takes a sharp intake of breath.

“Do you remember the Mt Asama eruption in 2003?”

“Huh? That’s a little off-topic, but, yeah. It was a minor one, right?”

“Mhm. But the resulting landslide took 11 lives.” Iwaizumi is silent, until his realises what Matsukawa means.

“You were there. 15 years ago, you were- were one of the kids who got pulled out alive.” Matsukawa nods, resting his chin in Iwaizumi’s hair, more like he’s trying to hide.

“I carried three little orphan babies to the nearest orphanage. They weren’t more than a couple of months, Iwaizumi… Kunimi was older, but still just a _baby_. I couldn’t turn them down as interns after seeing their place of birth. I lied about having 200 applicants so they wouldn't think they were bothering me.”

“Ah…” 

“It doesn’t end there. They- Kindaichi lost both adoptive parents in another eruption five years ago, and Kunimi lost his foster sister to ash inhalation just last year. They were determined to be the volcanologists of tomorrow, to stop anyone ever losing their loved ones again.”

“I- I see…” He doesn’t know what to say. There’s something very personal, very soft about it all, and Iwaizumi worries he might shatter that moment. He doesn’t need to, as a large chuck of rock landing close by does that for him.

“Holy fuck, I _hate_ explosive types.” Matsukawa laughs quietly, unintentionally pulling Iwaizumi closer to him, worried he’s not completely under the rock. Iwaizumi doesn’t mind. The arms around his waist remind him he’s not alone, he doesn’t have to do this alone.

He wouldn’t wish this on anyone, but… It’s nice to have Matsukawa there for him.

They sit there, chatting quietly as the ash rains down harder, cloaking the ground with a light grey layer, rocks from the cone thudding into it, and at one point, a stream of lava snaking past before dripping into the ocean.

“Is it bad that I wanna stick my hand in it?”

“Matsukawa, _don’t you dare_.” 

“But I would _lava_ know the feeling than not.” Much to Iwaizumi’s relief, he doesn’t. But he _does_ keep moving towards it as if he’s going to poke it, Iwaizumi slapping his hand each time.

Before he can lose his patience, however, he becomes aware that the volcano has gone quiet.

“Do you think it’s over for now…?”

“Possibly, though we have no idea when it’ll start again.”

“Because I really want to grab a lava sample. And some fresh pumice. Imagine the jealousy on Oikawa’s face.”

“Uh-huh, because you’re totally gonna risk your life to flirt in that strange, show-off way you both do.”

“It’s not flirting!!!” 

“But you do flirt.”

“...” Matsukawa laughs at the silent confirmation, before cutting himself off abruptly. 

“You hear that?”

“... If that’s the boat, I’m going to throttle the captain for being so reckless.” A horn sounds from just out of sight, not quite on the other side of the island, and not quite where it had been originally. Iwaizumi scowls.

“I going to throttle the captain.” But if the boat is here… They must be safe to emerge. It’s likely they won’t have much time, so after quickly checking there’s no rocks falling in the area, they bolt towards the rocky edges of Nishinoshima, careful to jump over the stream of lava.

“Iwa-chan! Mattsun!” Oikawa waves from the back of the boat, and Iwaizumi lunges towards him with a roar that’s part angry, part relieved, whilst Matsukawa carefully boards the deck and sends a thumbs up to the captain to _get them out of here_.

“You idiot, Oikawa, you idiot!” 

“Ow, ow! Don’t hit me! Iwa-chan!” 

“You were _safe_ , why would you come back?!” Oikawa lets Iwaizumi punch his shoulder a couple more times, each one weaker until it’s no more than a pat, until Iwaizumi is burying his face in Oikawa’s collarbone and sobbing.

Oikawa gently hugs him, pulls him close, and opens his other arm for Matsukawa, who watches with a wobbling lip and watery eyes, before accepting it. He doesn’t cry, like Iwaizumi, but Oikawa feels a couple of blinked away tears before Matsukawa speaks, voice low and unsure.

“Are the kids…?”

“They’re okay. Makki’s looking after them on the shoreline. The poor things were so shaken, they seemed pretty convinced they’d never see you again.” Matsukawa sniffles, wiping his sleeve over his mask as if that would do anything.

“I don’t blame them… I’ll make it up to them though. Promise.” Iwaizumi pulls away from Oikawa to remove his gloves, mask, and goggles before furiously wiping at his face.

“Treat us to ramen…?”

“Hey, I said I’d make it up to the _kids_!” Oikawa only grins, giving Matsukawa’s arm a friendly nudge.

“I’ll cover it, Mattsun~. We’ll all go out tonight, as a celebration that we all made it~!”

When they get back to the mainland, Hanamaki makes sure to punch both of his friends, before Kindaichi and Kunimi rush in to cling to their mentor, desperately, as if they’re never going to let go.

They’re only _15_ , but they’ve seen so much tragedy, so Matsukawa gently hugs them back and promises it’s okay, everything’s okay, he’ll never take them somewhere that dangerous again.

Nishinoshima was a harsh, unforgiving landscape with an explosive climate, but Iwaizumi was sure they would all return to it someday.

**Author's Note:**

> I GODDAMN LOVE VOLCANOLOGY.  
> Hope you loved this fic just as much!!!
> 
> Please kudos and comment!   
> Bonus: What's your favourite volcano?


End file.
